The skinny: Sparks, a 38-year-old knuckleballer, has been tough on the Padres this year, allowing five runs over 20 innings in three starts and one relief appearance for a 2.25 ERA. Peavy will be making the first start of his career on three days' rest. He is 1-6 lifetime against Arizona with a 10.91 ERA.
Beyond the box score

Linebrink out: A viral infection sent Padres reliever Scott Linebrink to urgent care yesterday and kept him away from Petco Park. Linebrink is suffering from fever and weakness, said assistant trainer Jim Daniel.

Tour de force: Saturday is "jersey day" for the Padres, with players wearing replica jerseys to the ballpark. Peavy showed up yesterday wearing a replica Lance Armstrong yellow jersey from the Tour de France – complete with the riding shorts.

Diamondbacks honors: San Diego product Carlos Quentin, an alum of University of San Diego High, has been voted Arizona's Minor League Player of the Year. A right fielder Quentin, 22, had a combined .977 on-base and slugging percentage in Double-A.